Element superclass is always HTMLElement #168
Description
Description
No matter which parent your class have, iron-doc-element always displays HTMLElement.
If you try to replace superclass from the source JSON with another value, a computed reference in iron-doc-element will lead to https://baseurl/mixins/Superclass which is pretty weird. I'm not saying that it should find the real source URL of my superclass, but it's definitely shouldn't point to mixins.
class MyCustomElementExample extends MySuperclass { ... }
Expected outcome
The actual superclass is shown and its link does not refer to mixins.
Actual outcome
The HTMLElement superclass is shown.